


Making Headway

by tarnishedpeonies



Category: Transformers - All Media Types, Transformers Animated (2007)
Genre: M/M, Oral Sex, Sticky, Sticky Sexual Interfacing
Language: English
Status: Completed
Published: 2021-01-13
Updated: 2021-01-13
Packaged: 2021-03-17 13:40:23
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,989
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28725993
Author URL: https://archiveofourown.org/users/tarnishedpeonies/pseuds/tarnishedpeonies
Summary: Sentinel may have temporarily lost his body, but his processor is whole and this one opportunity he never thought he'd get.
Relationships: Optimus Prime/Sentinel Prime
Comments: 4
Kudos: 32





	Making Headway

Ratchet looked at the body on the slab in front of him, then squinted at Optimus - rather, the head Optimus was carrying, who had been complaining _loudly_ that he was ready to reconvene with his body. Ratchet then looked back at the body, and Optimus felt a glitch of stress when the old medic shook his head. “No, no way Optimus. Damage doesn’t look that bad on the outside, but I don’t know what all needs repair. Could have some connections loose, or damaged. So until I’ve got this body back in condition, you’re just going to have to keep Sentinel with you.”

The loudest part of Sentinel. “Of course Ratchet, whatever you think is best,” his chipper vocalizer mismatched the down-spiral in his mood. This would be better for Sentinel, but it meant continuing to carry Sentinel everywhere. The mech didn’t like him - but he liked the rest of Optimus’ crew even less, and his crew wasn’t even supposed to know. Ratchet was a grudging exception. “Let me know when you’re done and I’ll bring Sentinel back.”

“I hate this,” Sentinel griped, predictably. Optimus put a hand over his mouth, dealing with the brief series of muffled exclamations until his fellow prime quieted. Moving quickly through the hallway, Optimus ducked into his room and closed the door, setting the lock while sending a communication to his team that he would be unavailable the rest of the night. Unless it was an emergency.

With any luck, this time they’d understand that did not mean ‘Prowl and Bee are fighting’. Again.

“Why did you bring me in here. It looks filthy and it smells,” Sentinel continued complaining once Optimus’ hand was off. “Are we going to be in here all night? I hope your medic doesn’t work as slow as he talks. This is literally the worst **ever** , and if we hadn’t followed that bad tip I would never be in this position.”

“This is the only place the others won’t hear, or _see_ you,” Sentinel’s biggest concern of course. “Though they might get suspicious if you keep yelling at top of your vocalizer,” Optimus pointed out. “Also I don’t want you in here all night either, but if we leave Ratchet alone, he’ll get his work done faster. And you can be on your way sooner.” Well, that seemed to do the trick. Silence stayed between them, and with Sentinel’s head tucked in the bend of his arm Optimus stood on the edge of his berth, which lowered horizontal. “Now get some rest.”

Optimus figured he deserved a stasis cycle. It couldn’t hurt Sentinel either. Even with his former friend, now rival, tucked against his paneling Optimus started to feel the pull of a satisfying stasis slow his systems. His optics just off-lined when he heard Sentinel ask timidly, “Hey Optimus?”

He hoped that sigh was internal before answering, “Yes, Sentinel?”

“Remember that time in academy, when you and Elita and I went,” oh not this again, “to that club and got so overcharged we ended up falling asleep in the shuttle together?” Admittedly not where Optimus thought Sentinel was going with that, but he’d take it.

“You were so overcharged you thought the shuttle was your carrier. Elita took video because she knew you’d never believe it if we just told you the next day. And I purged just over the boarding ramp before finding a piece of free real estate on the floor and passing out.” It was _not_ one of their collectively finer moments. Only Elita-1 had really escaped the evening without any embarrassing experiences.

Sentinel’s head vibrated in the bend of his arm with a powerful hum. “Right, yeah, that did happen,” Sentinel conceded. “And then the next day while we still had that buzz from the overcharge we fragged. Remember that?”

Oh. That was not where Optimus thought Sentinel was leading this conversation, and it only made him more cautious. “Yes,” he admitted tentatively, before pulling Sentinel’s head up so they could lock optics. “Why?”

Shifting away, Sentinel’s optics shifted back to Optimus before his faceplates warmed and turned a shade. “I was - just thinking that I never got you back on that spike sucking I promised when I overloaded on your face.” Now Optimus was _staring_ , and Sentinel began stammering. “Come on, don’t look at me like that! I just,” his vocalizer quit briefly before it reset. “I just. Want to try it.” That red spread to almost Sentinel’s entire face, and Optimus had to admit it wasn’t his color. “Please.”

“You’re just a head,” Optimus pointed out. That meant reciprocating would be impossible, and more importantly, “and we haven’t been on the best of terms lately. Why do you even want to do this?”

The question was met by Sentinel’s attempt at pleading eyes. He’d even said please, which convinced Optimus something was off.

“I’m going to take you back to Ratchet. Your processor must have been knocked hard at some point.”

“No _wait_ ,” Sentinel pleaded. “I just…don’t get opportunities like this every day.”

Optimus stared, any number of ways to tell Sentinel that as an understatement failing inspection before he blurted out, “I hope not.”

Sentinel’s faceplates furrowed and he stammered again, struggling through his next statement. “I…want to. I want to do this, like this. To…give someone - who won’t take advantage of me,” and Optimus wouldn’t, Sentinel had him there, “the opportunity to…have me. Like this. Complete control,” Sentinel tacked on at the lowest possible volume his vocalizer could make. “Please.”

Twice now he’d said it, and Optimus wasn’t convinced. “It’s _weird_.”

“Not as weird as you being attracted to a spiderbot.” He almost threw Sentinel across the room. It must have shown in his expression. “Wait! No, I just - I couldn’t do this with anyone else.” Silence lengthened between them again, before Sentinel finally offered, “It would shut me up.” At this point the promise of silence was almost enough to pressurize his spike, but Optimus gave it a second thought; did he want it? He wasn’t proud imagining how good it would feel to spike Sentinel’s face after some of the scathing things his fellow prime had called Optimus earlier that day.

He _was_ imagining it though, and Sentinel was offering it to him on a platter. It can’t be the worst thing Optimus has ever done. “Okay,” he agreed, cupping Sentinel’s head a little gentler. “But you have to start being quiet right now.” Asking Sentinel for complete silence would be too much, and Optimus knew it. “The only words you can use - are yes, no, and my name.” That way if he had to ask a question he was covered, and - well the last part, just to put a little sodium chloride in the wound. “Do you understand?”

“Yes.”

Sentinel didn’t sound very sure. Optimus pressed a thumb along his lower lip plate, slowly. That chin was too large to avoid being caressed by his palm, and he suppressed a smile when Sentinel moaned; he hated his chin, and Optimus knew this was part of why. “Yes, what?”

He huffed before a light growl passed his lips, lightly vibrating Optimus’ finger. “Yes… _Optimus_ ,” he finally conceded, faceplates red. Optimus rewarded him, pressing that thumb between his lips and touching Sentinel’s glossa, rolling the digit back and forth while humming softly. Arousal felt distant, until Optimus recalled the night in question. He’d wondered at the time, what it’d felt like for Sentinel. What it might feel like for himself. He couldn’t indulge those curiosities with his team as their leader. It’d be wrong.

With Sentinel, another prime? Neither could order the other without agreement. Optimus couldn’t say they stood equal right now, but - Sentinel had begged and Optimus agreed. Framing it like that, recalling the fire in his lines as he’d bobbed up and down on Sentinel’s spike, listening to the moans…that helped. His panel slid back, pressurizing as Sentinel took a hint, lips closing to suck on Optimus’ thumb.

It wasn’t fire, but a crisp tingle moved through his lines as Optimus sighed. His thumb pressed and swayed, feeling the slick in Sentinel’s mouth, imagining that warmth on his spike. The head pressed gently against the flat panel hiding Sentinel’s connectors, sliding back and forth against the warming metal. A loud, muffled hum brought Optimus’ attention down, where Sentinel’s optics were dimmed. It was _almost_ cute, reminiscent of a different time.

Pulling his thumb back, Optimus chuckled softly at the insistent pop when he was freed, lubricants stringing away. He wasn’t giving Sentinel a chance, pressing that wet thread against his faceplate as he brought the prime’s face lower. Optimus hadn’t expected the way Sentinel opened his mouth for more; begging again, without words, and it was too tempting to resist leaving him within inches of his goal. Sentinel’s glossa wasn’t long enough to reach either, which made him grin.

“Optimus!” Begging again, _with_ words. That brought a little heat to his lines, but he waited for Sentinel to open his mouth again, to pull that mouth around his spike. A muffled word, it might have been his name, and a vibrating moan followed shortly. Primus. It didn’t take long for Sentinel to start working on his own, glossa pressing and shifting along his length, the mech still muttering and moaning around Optimus’ spike. Those cylinders on the side of Sentinel’s head stood at full attention, and Optimus found himself touching them gently.

It felt nice, and Optimus still needed more. More - “Ah!” - movement, yes, that exactly. He rocked Sentinel’s head back gently, pulling it back forward after a moment, feeling the mech adapt to the movement while Optimus found his rhythm. It felt good, though it wasn’t long before Optimus found his hips twitching, bucking occasionally when Sentinel’s lips kissed his plating. It couldn’t have been too deep based on the noises Sentinel continued making. All of it helped drive Optimus mad with pleasure.

He needed to overload. 

There was no thought when Optimus, keeping Sentinel pressed as close as possible with one hand, used the other to shift until he had Sentinel’s head supported on the berth. His hand moved to steady Sentinel, fingers laced in those fanned cylinders, making sure he stayed exactly where Optimus wanted him as he started thrusting. Soft. Warm. _Wet._ Good as any valve, and Optimus couldn’t keep a shiver of excitement from dancing up his spinal struts at remembering who it was, mouth full, beneath him. “Sentinel,” he warned with a moan as the charge raced to a tipping point.

Everything happened at once, the charge crackling off, hips burying his spike as deep into Sentinel’s face as possible, transfluid pumping out in bursts as Sentinel objected ineffectively beneath him. Incredible. Optimus realized he had no more transfluid to give long before his hips slowed and his spike started depressurizing. “Oh, Sentinel. I have to admit you’re - better than I thought to give you credit for.” Sitting back on his pedes, Optimus looked down at the head - mouth full, with nowhere to put it. He couldn’t spit. He couldn’t swallow. He couldn’t _talk_ without sounding ridiculous.

Optimus smiled. “I’ll let you stay here and rest, Sentinel. You’ve had a trying day.” Backing off the berth slowly, Optimus caught a couple gurgled protests and started whistling over the sound as he picked up a cloth to clean himself off. Sentinel could stew for a bit, enjoy the flavor of his hard work while Optimus caught some stasis somewhere else in the room, or elsewhere on-base. He’d get Sentinel cleaned up when Ratchet called him back, they’d get him reattached, and that would be that.

In the end Sentinel would get his body back, be bossy as ever, and Optimus would be the object of his ire. No one would be the wiser to what happened tonight, because Optimus wouldn’t talk, and Sentinel wouldn’t spill.

**Author's Note:**

> No, Ratchet doesn't know why Sentinel's body did that while he was working on it. No, Ratchet isn't asking.


End file.
